Process and apparatus for treating dioxins

ABSTRACT

A process and apparatus assuring low costs and high efficiency in practicing refuse incineration. A applying electromagnetic wave of a frequency band resonant with rotation or vibration of a specific substance e.g., dioxins molecule, thereby to heat the dioxins molecule selectively up to high temperature to remove the dioxins molecule by decomposition.

FIELD OF THE INVENTION

[0001] This invention relates to process and apparatus for treating aharmful substance, in particular, to process and apparatus for treatingdioxins such as 2,3,7,8-tetrachlorodibenzo-p-dioxins.

BACKGROUND

[0002] Dioxins are referred to, for example, the following literature.

[0003] Reference 1: “An introduction to dioxins” translated by RyotaFujiwara and Higashi Kido, edited by Masatoshi Morita, and published byJESC (Japan Environmental Sanitation Center) on June 1991 (Originaldocument: U.S. EPA Research Reporting Series, “Dioxins”).

[0004] 1. <Structure and Production Cause of Dioxins>

[0005] Dioxins were synthesized at first in Germany in the mid-19thcentury, but their strong toxicity wasn't known until 1950s. Ever since,the toxicity of dioxins has been widely known through the news offrequently broken out occupational diseases and environmental pollution,Vietnam War and etc. in connection with dioxins, and studied widely. In1990s, it has been known that dioxins spread out widely around theirsurroundings through the incineration of refuse/waste and otherprocesses. Consequently, studies on the influence, measurement andremoval method of dioxins have been suddenly required. To attain thisend, these studies have become active, and the number of papersconcerning dioxins is rapidly increased now.

[0006] At first, an outline of dioxins is given below. General chemicalstructure of dioxins maybe represented as follows.

[0007] To the substitution sites of the numbers 1 to 4 and 6 to 9,chlorine and other halogen atoms, organic radical and hydrogen atom maybe bonded. These kinds of compounds are usually called as “dioxinshomologues”, and 77 or more kind of isomers belonging thereto are known.

[0008] Among these dioxins homologues, the most remarkable compound inthe field of environmental science and others is2,3,7,8-tetrachlorodibenzo-p-dioxins (C₁₂H₄Cl₄,₂; which is abbreviatedas “TCDD” to the 2-, 3-, 7- and 8-positions of which chlorine atoms arebonded.

[0009] TCDD has no functional group of high reactivity, thereby showingextremely high chemical stability, belongs to molecules soluble in highmolecular weight paraffin, dissolves very little in water and most oforganic solvents, and exhibits a colorless crystalline solid at roomtemperatures.

[0010] For synthesizing dioxins, various processes are known. Theirreaction temperatures range from 180 to 400° C., and the reactionproducts are stable up to 700° C. Accordingly, it is necessary to applyheat up to temperatures of not less than 800° C., or of not less than1150° C. under certain conditions to decompose dioxins.

[0011] Typical organic compounds potentially by-producing dioxinsinclude chlorophenols and their derivatives; and hexachlorobenzene.These compounds are classified into the following 3 large groups.

[0012] The first: polyhalogenated phenols (1st group).

[0013] The second: o-halophenols, and halogen- and other-substitutedphenols (2nd group).

[0014] The third: substances not classified into 1st and 2nd groups butpossibly producing dioxins (3rd group). However, the possibility is lowthat the substances of the 3rd group produce dioxins.

[0015] As a material belonging to the above groups and commerciallyproduced not less than 1,000 pounds in a year in U.S., there are known12 kinds of chemical substances belonging to the 1st group, 16 kinds ofchemical substances belonging to the 2nd group, and chemical substancesof 50 kinds or so belonging to the 3rd group.

[0016] By the process for preparing pesticides such as insecticide andherbicide, dioxins are potentially by-produced. A large number ofagricultural chemicals are known that contain dioxins at highconcentration.

[0017] Recently, the precision of measuring dioxins has been improved toenable measuring a very small amount of dioxins. Consequently, thediscovery has been made that dioxins are contained in agriculturalchemicals and also in a basic chemical material of chlorophenolsalthough the content contained in the latter material is very little.Moreover, it is known that not only these substances but also industrialwastes generated in the course of producing the same contain dioxins athigh concentration. The aforementioned chemical material is used as apreservative of foods, crude rubber, leather or the like, or, otherwiseas a raw material for preparing insecticides.

[0018] In addition to the above, these are applied directly to the humanbody in disinfecting swimming pool, home, hospital, bathroom and etc.All of these compounds are registered as an insecticide in EPA(Environmental Protection Agency) in U.S.

[0019] The fact that dioxins are produced according to the above processhas been hitherto known. Recently, owing to the press and other media,attention has been paid to production and diffusion of dioxinsoriginated from “combustion source”, that is, waste/refuse incinerationor other incinerating facilities. This finding is much owing to theimprovement in the precision of measuring dioxins in Japan. However,before this time, 17 kinds of dioxins were detected by the analysis offloating particulate matter collected out of 3 municipalrefuse-incinerating facilities in the Netherlands in 1977. Diffuseddioxins are contained in combustion gas and fly ashes.

[0020] On the synthesis of dioxins through the step of burning, chemistsof the Dow Chemical Company considered that many precursors of dioxinsare produced through a complicated process such as burning, andsuggested in 1978 that dioxins are synthesized naturally through thecombustion of natural materials. Then, many chemical substances of theprecursors have been studied until today.

[0021] It is necessary in decomposing dioxins by combustion at least toapply heat up to temperatures of not less than 800° C. and watch whetherdioxins are regenerated or not at temperatures ranging from 180 to 400°C. when the temperature of the resultant decomposition product becomeslowered. It is also known that dioxins contained in fly ashes neverdecompose without heating up to around 1200° C.

[0022] 2. <Dioxins Analyzing Method>

[0023] Because dioxins have very strong toxicity, microanalysis isrequired. General analyzing methods of dioxins include gaschromatography, mass spectrometry, UV spectrophotometry, ESR (electronspin resonance) spectroscopy, low temperature phosphorimetry and etc.There is no analyzing method now that can provide both high sensitivityand selectivity at the same time applicable to substantially all thesamples and surroundings.

[0024] It is said that the detection limit of dioxins is about 0.001 ppb(ppb: parts per one billion) at the present time. However, fluctuationsin the measured value, which are large especially at low concentration,arise depending on measuring system, person and etc. On account of this,it is important to standardize the measurement, and for attaining thispurpose, a joint study is started now by plural organizations such asresearch institutions and universities in Japan. Through the aboveactivities, the measurement in and of itself is accepted as one ofimportant research and development themes.

[0025]3. <Dioxins Exposure Accident to the Human Body>

[0026] Up to this time, there have been reported a lot of accidentscaused by dioxins. Among them, an accident that happened in Meda, Italyon Jul. 10, 1976 is very terrible. In this accident, 300 g to 130 kg ofdioxins were scattered around to pollute their surroundings and to cause134 cases of children suffering from acute toxicity of chloracne.Further, 170 labors were directly polluted, and hundreds of animals weretaken ill and killed in the worst case.

[0027] It is said that the largest-scale pollution which has everhappened in the world until now is the pollution caused by the UnitedStates Air Force burning 10,400 tons of a defoliant containing dioxinson the Pacific Ocean in 1977, and that this fixed the dioxins'background of the world.

[0028] Further, it is said that the birth of many malformations found inVietnam is due to pollution caused by spraying the defoliant. However,some U.S. report told that there is no correlation between the sprayeddefoliant and the birth abnormality. It is said that the largest-scalepollution caused in Japan is due to herbicides sprayed on waterrice-fields.

[0029] Moreover, it is reported that many foods contain dioxins. It isalso reported that dioxins are contained in: fishery products caught inSouth Vietnam; garden vegetables, fruits, milk and etc. which werepolluted in the accident caused in Italy in 1976; and mother's milktested recently not only in Japan but also in European countries.

[0030] The toxicity of dioxins is the strongest of all synthesizedchemical substances (stronger than sodium cyanide). It may be no toxicmaterial having stronger toxicity per molecule than that of dioxinsexcept botulinus toxin.

[0031] It is reported that the exposure of dioxins causes diseasesincluding melanoderma, myalgia, polyneuritis, cold tolerance loweringdisease, liver malfunction accompanied by hepatomegaly in addition tothe aforementioned chloracne. There is also a report referring toanother diseases caused by the application of dioxins such as atrophy ofthe thymus, atrophy and necrosis of the testis, generation of abnormalspermatocyte, hypertrophic gastritis and etc. It was found that thesediseases result from occupational exposure of highly densed dioxins anddioxins exposing test to Primates. Further, it was found by the animaltest that dioxins exhibit teratogenicity, embryotoxicity,carcinogenicity, cocarcinogenicity, genotoxicity and other symptoms.

[0032] Recent research report tells that dioxins taken into the body aremetabolized slowly. The rat test shows that the half-life of theexcretion is about 17 days and that dioxins are discharged out throughfeces, urine and breath. This measurement has little error in spite thatmicroanalysis is employed because of using a radioactive isotope.Further, the toxicity of dioxins has been studied biochemically, andmainly, the toxicity due to enzyme inhibition has been made clearthereby.

[0033] 4. <Decomposition and Migration of Dioxins in aDioxins-Containing Environment>

[0034] It is reported that biodegradation (organic decomposition by thecomplicated works of organisms) of dioxins is considerably little, butthis doesn't mean that dioxins are never biodegraded. The result on theabove study is different depending on the reporters and does give noclear solution now.

[0035] It is known that light of UV region is the most effective tolight-decomposing (cutting a chemical bond by light) dioxins. Thesunlight decomposition is the most effective of all the naturaldecompositions. On the other hand, there are many research reportstelling experimental results of light-decomposing dioxins under variousphysical conditions.

[0036] Further, the condensation of dioxins also has been observed inthe body of animals.

[0037] It is reported that plants also condense dioxins contained insoil, but the concentration of dioxins contained in fruits and leaves islower than expected, which may probably be due to the sunlightdecomposition of dioxins.

[0038] 5. <Dioxins Treatment and Purge/Purification>

[0039] The treatment of Dioxins has been put into practiceconventionally by dumping or filling into a disused pit or tunnel beforecovering the surface of the port with concrete, or by dumping into seaafter solidification with concrete.

[0040] It is said that the cost accompanied by the above treatment isabout half a million dollars in U.S. for treating the quantity of 3,000barrel (1 barrel: 120 to 160 litters) held in drum cans so as not toleak out.

[0041] There are 3 methods mentioned below which have beenconventionally applied on a large scale for removing dioxins.

[0042] The first method is removal by incineration that has beendeveloped for the purpose of treating harmful substances having strongtoxicity such as agricultural chemicals. The decomposition ratio isdifferent depending on operational conditions of an incinerator. It issaid that it takes 21 seconds at 700° C. and that a decomposition ratioof 99.5% can be achieved at 800° C. The United States Air Force put thelargest-scale treatment into practice on the center of the Pacific Oceanusing a large-sized incinerator mounted on a chemical tank vesselstoring 10,400 tons (not less than 2 million gallon) of herbicideoranges. Its operational conditions are reported as follows. Meanburning temperature: 1,500° C., furnace residence time: 1 second, andthe concentration of oxygen contained in flue gas: not less than 3%. Thecombustion efficiency under these conditions was estimated at 99.9%.

[0043] As an extension of the removal by incineration, a burning testusing molten salt was put into practice in 1975 in U.S. This method hasthe merit of letting a sample keep at high temperatures for a long time,and as a result of the test, a high decomposition ratio was reported.

[0044] Further, decomposition by applying high frequency plasma wasreported in 1978 at first. This method is for decomposing dioxins in ashort time due to the high reactivity of high temperature plasmaresulting from oxygen atoms, and its laboratory-level research was putinto practice. It is reported that this method is effective todecomposing not only dioxins but also other stable chemical substancessuch as PCB etc.

[0045] As a decomposition method, photodecomposition is proposed inaddition to the combustion. This is a method of applying UV light to asample kept in an easily photodegradable state. Recently, proposal andexperiment have been made to promote the decomposition of dioxins byemitting light of a frequency resonant with the dioxins to cause theisolation of the atoms of the dioxins (corresponding to IR wavelengths)into combustion gas.

[0046] The treatment with radial rays also has been studied. This can beregarded as one of the extended photodecomposition technologies. Byapplying 10⁶ rad of radial rays to dioxins mixed in a solvent ofethanol, acetone, dioxisane or the like, a decomposition ratio of 97%was achieved. However, it was pointed out from the results yielded by aseries of experiments that this method is extremely ineffective fordecomposing the dioxins mixture and causes the increase of costs. Allthe aforementioned methods belong to a physical method.

[0047] In addition to the above methods, a method of treating dioxins bycombustion after absorption by activated carbon also has been studiedfor treating low enriched dioxins, but this method isn't applied on alarge scale now.

[0048] The second method is a chemical one, and plural methods belongingthereto have been proposed.

[0049] These methods include, for example,

[0050] a) ozone treatment (blowing ozone into a solution containingdioxins),

[0051] b) decomposition with iodine chloride (decomposing dioxins byadding iodine chloride thereto after condensing dioxins and changing thecondensed dioxins into colloid with a surfactant),

[0052] c) wet air oxidation (putting a sample into water before treatingunder pressures ranging from 40 to 140 atmospheres at temperaturesranging from 150 to 350° C. Recently, this method is called as “criticalwater treatment”),

[0053] d) catalytic dechlorination (reductively depriving chlorine atomsfrom dioxins using a catalyst), and the like.

[0054] However, all of these chemical treatments are in an experimentalstage at pilot plant now, and not put into practice on a massive scale.Their characteristic point is to treat the whole contentssimultaneously, and they become effective in case of containing dioxinsat high concentration.

[0055] The third method is biological treatment. For example, dioxinstreatment with bacteria is still in the basic research level now, andresearches applying this treatment to soil, drainage system and the likeare going on. Then, a water treatment apparatus is proposed that hasbeen devised in many ways for increasing the activity of bacteria insoil. These researches are under way under the prerequisite of treatingat low concentration.

[0056] Currently, dioxins contained in agricultural chemicals and thelike have been checked very strictly to decrease their amount. However,the generation of dioxins in a refuse incinerator becomes a big subjectof discussion now. This depends on a reason that many chemicalsubstances become wasted out of home as a standard of living is improvedto generate dioxins proportionally thereto in the incinerationfacilities through the refuse incineration process.

SUMMARY OF THE DISCOLSURE

[0057] The following is explanation of the problems occurring mainly incase of putting the aforementioned conventional methods ofremoving/treating dioxins into practice in a refuse-incineratingfacility or the like.

[0058] In a refuse-incinerating facility, a great number of chemicalsubstances are contained because of treating by combustion of variousrefuse wasted out of home and etc. Accordingly, there is a possibilitythat the chemical substances of the 1st and 3rd groups explained in theaforementioned paragraph 1 are mixed.

[0059] Further, in a refuse-incinerating facility, combustiontemperature cannot be elevated so much. This depends on a reason thatrefuse is not always fit to be burnt. Accordingly, the combustiontemperature may be around 800° C. at most. Further, the residence timeof the combustion gas cannot be prolonged so much. Accordingly, it isexpected also by the past experiments that the possibility of generatingdioxins is high. It is recognized now that the surest treating method isto attach an afterburner to the chimney of an incinerator, to injectfuel such as petroleum and the like through the afterburner, and then toburn again at high temperatures.

[0060] Taking the above matters into consideration, the method stated inthe above paragraph 5 is checked again as follows.

[0061] At first, the high temperature burning method is in a sense thesame with that put into practice by the United States Air Force in thePacific Ocean subject to being directed in all refuse-incineratingfacilities. However, it takes too much cost for burning refuse byapplying this method. This is caused by fuel cost required for heatingup to high temperatures and the short life of an incinerator shortenedby the high temperatures. Accordingly, it is difficult to put thismethod into practice.

[0062] On the other hand, the method using a molten salt or plasma iscertainly effective in case of containing dioxins at high concentration,but this method also requires too much operational cost. Particularly,in case of applying plasma, temperature of the plasma-emitted spotexceeds ten thousand degree. This method is not practicable because highcost is required for raising temperatures. Accordingly, it is actuallydifficult to apply this method to refuse incineration. In case ofraising up the temperature of electrons constituting plasma partially,it can be easily imagined that the decomposition ratio of dioxinsbecomes lowered.

[0063] Conventionally proposed photodecompositions, i.e., methods ofapplying UV rays, radioactive rays and IR rays are studied now. Amongthem, so far as the radioactive rays are concerned, introducing aradioactive generator, which emits very strong radioactive rays, intousual civil facilities like a refuse incineration facilities in itselfcauses problems in control and safety and substantial rise in treatingcost thereby.

[0064] Though UV and IR rays are much absorbed by other molecules thandioxins in an incinerator (the absorbance of IR and UV rays is basicallylarge in the air), improvement in efficiency of decomposing dioxins isexpected if dioxins are contained at high concentration in the air.However, in this method, it is necessary to set up special lamps andlaser oscillators for the emission of UV or IR rays, and the fact thatthe oscillating tube by itself is high in cost causes a big problem.

[0065] On the other hand, considering the cost of activated carbon andthe property that activated carbon absorbs chemical substances inaddition to dioxins, it will be necessary to review the aspect of costsarising in the separation by absorption with activated carbon in thefuture.

[0066] Next, the chemical and biological treatments referred to in theabove paragraph 5 will be considered as follows. In case of the chemicaltreatment, all the contents are principally treated at the same time.Accordingly, refuse, which does not require such treatment in itself,are also treated inevitably. Thereby, it is expected that costs becomevery high.

[0067] On the other hand, the biological treatment cannot be applied ina refuse-incinerating facility because of using bacteria.

[0068] Accordingly, the present invention has been made in considerationof the aforementioned problems involved in the prior art. It is anobject of the present invention to provide a process and apparatus fortreating dioxins that assure low cost and high efficiency and aresuitable for application to refuse incineration.

[0069] According to a first aspect of the present invention,decomposition of objective chemical substances to be removed such asdioxins is made by applying electromagnetic wave to an objectivechemical substance and/or a material containing the objective chemicalsubstance to heat the objective chemical substance to be removedselectively. According to a second aspect of the present invention,decomposition of dioxins is made by applying electromagnetic wave tocombustion gas generated and held in a refuse incinerator to heatselectively dioxins contained in the combustion gas. Further,decomposition of dioxins is made by applying electromagnetic wave to flyashes in a refuse incinerator to heat selectively dioxins contained inthe fly ashes.

[0070] According to a third aspect of the present invention, anelectromagnetic wave oscillator is provided so as to applyelectromagnetic wave emitted to a dioxin-containing combustion gas in anincinerator. Other applicable means and methods in the present inventionfor solving the aforementioned problems are just as disclosed in each ofthe appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0071]FIG. 1 is a view showing the 1st example of the constitution ofthe inventive incineration.

[0072]FIG. 2 is a view showing an electromagnetic wave cut filteremployed in the 1st example.

[0073]FIG. 3 is a view showing the 2nd example of the constitution ofthe inventive incineration.

[0074]FIG. 4 is a view showing the 3rd example of the constitution ofthe inventive incineration.

[0075]FIG. 5 is a view showing the 4th example of the constitution ofthe inventive incineration.

[0076]FIG. 6 is a view showing the 5th example of the constitution ofthe inventive incineration.

[0077]FIG. 7 is a view showing the 6th example of the constitution ofthe inventive incineration.

[0078]FIG. 8 is a view showing the 7th example of the constitution ofthe inventive incineration.

[0079]FIG. 9 is a view showing the 8th example of the constitution ofthe inventive incineration.

[0080]FIG. 10 is a view showing the 9th example of the constitution ofthe inventive incineration.

PREFERRED EMBODIMENTS OF THE INVENTION

[0081] The embodiments according to each aspect of the present inventionare just as disclosed in the corresponding dependent claims appended.The details of the inventive embodiments will be further explainedbelow. The present invention provides a completely novel electromagneticincinerator capable of decomposing and treating special chemicalsubstances, in particular, dioxins among all by applying electromagneticwave thereto.

[0082] The principle in the inventive treatment of the special chemicalsubstances, in particular, dioxins among all is to selectively heat onlyspecific molecules such as dioxins up to high temperatures by applyingelectromagnetic wave, which has a frequency band resonant with rotationor vibration of the specific molecule, to the molecules held in anincinerator. Namely, the whole combustion gas isn't raised up but onlyspecific molecules are raised up to high temperatures. Accordingly, itis unnecessary to raise the temperature of the whole combustion gas sothat large power is no more necessary.

[0083] Further, the present invention has a feature that it is possibleto heat up the objective substance to very high temperatures because inprinciple there is no upper limit of temperatures up to which a heatingobject is heated likewise the case where high-frequency emission isapplied to produce plasma.

[0084] The wavelength of electromagnetic wave applied in theconventional photodecomposition of the chemical substances such asdioxins ranges from UV to IR, which was made clear previously byexperiments.

[0085] On the contrary, in the process of the present invention,electromagnetic wave in the region of microwaves is applied like anelectronic oven. Inside the electronic oven, electromagnetic waveresonant with the rotation frequency of water is emitted to heat watermolecules selectively and never to heat vessels nor cooking utensils.Even if the conversion of electric energy into electromagnetic radiationis low (usually, 35% or so), cooking time can be saved on account thatthe energy conversion is finally high as compared with the case ofwarming a cooking utensil and indirectly foods by heat using gas orother fuel.

[0086] The conventional method of applying IR rays also directlydecomposes chemical substances such as dioxins according to theprinciple of resonance absorption, which, however, is largely differentin the following two points of effects.

[0087] (1) At first, IR rays are largely absorbed by the air andcombustion gas. Accordingly, other molecules absorb IR rays beforespecific molecules such as dioxins do so. Consequently, efficiency ofthe decomposition is low.

[0088] In contrast with this, the electromagnetic wave applied in thepresent invention is little absorbed by general gas such as air and thelike.

[0089] (2) The second point relates to the efficiency in conversion ofelectric energy into IR rays. The oscillation frequency of a domesticelectric oven is 2.45 GHz, a magnetron is used for the oven, and theconversion efficiency is about 35%. Generally, the conversion efficiencyin case that electromagnetic wave is in the region of microwaves shows avalue of this degree. However, the conversion efficiency of laser andother oscillators is lower than this value.

[0090] The advantage of applying microwave is very great in view of theconversion efficiency like this.

[0091] Further, complicated molecules like dioxins are resonant with alarge number of frequencies. Accordingly, it is easy to prepare anoscillator capable of emitting microwave having a required resonancefrequency or frequencies.

[0092] In one aspect of the present invention, the inventive treatingapparatus has an electromagnetic wave oscillator, and specific chemicalsubstances (in particular, dioxins) are decomposed through the step ofapplying electromagnetic wave emitted by the electromagnetic waveoscillator to combustion gas generated and held in an incinerator andcontaining specific chemical substances such as dioxins.

[0093] The treating apparatus of the present invention may be equippedwith an electromagnetic wave filter for preventing (suppressing)electromagnetic radiation from passing through a chimney at a chimneysection for discharging the combustion gas. Further, the treatingapparatus of the present invention may have a cavity for applyingelectromagnetic wave positioned inside the chimney section fordischarging combustion gas generated and held in an incinerator upstreamof the electromagnetic wave filter. In this treating apparatus,combustion gas generated in the incinerator is introduced into thecavity, exposed inside the cavity to electromagnetic wave emitted by theelectromagnetic wave oscillator, and thereafter exhausted asincineration gas through the electromagnetic wave filter.

[0094] The electromagnetic wave (cut) filter (or shield) may be equippedwith plural open-ended metallic hollow pipes each aligned in the flowingdirection of the combustion gas. The diameter of the pipe is smallerthan the wavelength of the electromagnetic wave; with the length of thepipe being longer than the wavelength.

[0095] Moreover, the treating apparatus of the present invention mayhave a sensor, disposed in the chimney part, for detecting theconcentration of dioxins contained in the exhausted gas, and a controlunit for variably controlling the magnitude of electromagnetic waveapplied to the combustion gas generated in the incinerator depending onthe output of the sensor.

[0096] The treating apparatus of the present invention may be equippedwith a fan for scattering combustion gas and electromagnetic wave in theincinerator, and a motor for driving the fan.

[0097] Further, the treating apparatus of the present invention may havean electromagnetic irradiation unit applying electromagnetic wave to flyashes generated (and held) in the incinerator. With regard to the refuse(waste) treatment by applying electromagnetic wave, for instance,JP-A-11-29346/1999 (The term “JP-A” used herein means “unexaminedpublished Japanese patent application”) discloses an adsorbent,oxidative, catalytic agent, which can decompose harmful substances suchas dioxins in the course of refuse incineration to remove them and whichmake ashes harmless thereby, and a process for preparing same. In therefuse treatment disclosed in this document, ashes such as burned ash,fly ash are sieved to remove contaminants; dried by heating; pulverizedafter removing metals with a magnetic separator; mixed with rawmaterials of bentonite, zeolite, glass cullet and sludge-burned ashresulting from excretal and other sludges; granulated while beingmoistened after kneading to form a base material. The base material,after granulation, is treated by sintering and firing at temperaturesranging from 600 to 1300° C. after predrying. The thus treated basematerial is cooled down to 800° C. Thereafter, treatment of sterilizingand deodorizing is applied to the base material through the step ofexposing to electromagnetic wave or passing through an ozone atmosphere.In the above method, electromagnetic wave is applied for the sake ofsterilizing and the like. As such, the process never aims at decomposingand removing dioxins through the step of exposing dioxins contained infly ashes to electromagnetic wave of a frequency resonant with thedioxins molecule.

[0098] In one aspect of the inventive apparatus, the inside wall of theincinerator is made of ceramics; and the outside wall has a metallicmember made of electromagnetic radiation shielding metal.

[0099] Further, in the present invention, the refuse input port and thefly ash output port of the incinerator have a double door structure.

[0100] In the present invention, a re-combustion chamber for inputtingand combusting again the combustion gas may be installed to exhaust thegas re-combusted in the re-combustion chamber, and electromagneticradiation emitted by an electromagnetic wave oscillator may be directedin the inside of the re-combustion chamber.

[0101] In the present invention, fuel may be introduced into a cavitypositioned inside the incinerator to combust the combustion gas again.

[0102] In the present invention, a magnet field generator may bearranged around the re-combustion chamber and/or the cavity, andmagnetic field may be formed therewith inside the re-combustion chamberor inside the cavity.

[EXAMPLES]

[0103] Examples of the present invention are explained below inreference to the accompanying drawings. FIG. 1 is a view showing theconstitution of an electromagnetic incinerator (incineration-treatingapparatus) 100, which is one example of the present invention. Into theincinerator, refuse 108 is input through a refuse input port 108 havingdouble doors. The double doors are designed for preventing the leak ofelectromagnetic wave directed into the incinerator through the inputport. Also a portion out of which fly ashes 110 fallen down through asieve (mesh) 107 and accumulated on the bottom of the incinerator afterincineration are taken, i.e., fly ash output port 106 has also doubledoors. Though it depends on the scale of the incinerator, incinerationis usually performed in an incinerator after bringing refuse theretousing a crane or the like in such a manner as the refuse become easilyburnt while the operator monitors the burning state of the refuse heldin the incinerator by watching TV of industrial use or the like.

[0104] In one embodiment of the present invention, electromagnetic wavehaving a band of frequencies (microwave region), at least one of whichis resonant with dioxins molecules, is emitted by an electromagneticwave oscillator 103 toward the inside of the incinerator and applied tothe dioxins. A window made of heat resisting material (ceramic window104) is attached to the wall 102 to prevent combustion gas 112 fromflowing backward into the electromagnetic wave oscillator 103.Electromagnetic wave emitted by the electromagnetic wave oscillator 103is applied through the ceramic window 104 into the incinerator. Theelectromagnetic wave travels from the electromagnetic wave oscillator103 to the ceramic window 104 through an appropriate medium such ascoaxial cable, wave-guide or the like depending on the frequency-of theelectromagnetic wave. To simplify a drawing, single electromagnetic waveoscillator is shown in FIG. 1, but of course, plural electromagneticwave oscillators may be facilityd so as to surround the sidewall of theincinerator. Necessary shields are applied to the joint of theoscillator 103 and a wave-guide portion through which electromagneticwave oscillated by the oscillator is guided into the inside of theincinerator, to the joint of the guide and the wall 102 (ceramic wall),and to the joint of other two portions if necessary.

[0105] In the thus constituted embodiment, a dioxins molecule is heatedselectively in the incinerator by means of the electromagnetic wave.Consequently, the decomposition of the dioxins advances rapidly onaccount that a dioxins molecule is selectively heated up to hightemperatures although the mean temperature of the combustion gas isalmost the same with that in the conventional incinerator.

[0106] In one embodiment of the present invention, electromagnetic waveis introduced into the incinerator, and an electromagnetic wave filter(shield) 111, through which exhausted gas passes but electromagneticwave doesn't, is placed in the midway of a chimney 105 in order toprevent the leak of electromagnetic radiation out of the chimney 105.

[0107]FIG. 2 is a schematic view showing one exemplary constitution ofthe electromagnetic wave filter 111 placed in the midway of the chimney105. FIG. (2 a) is a cross-sectional top view of the electromagneticwave filter. FIGS. (2 b) and (2 c) represent cross and longitudinalsections of a metallic pipe 114. As shown in FIG. (2 a), theelectromagnetic wave filter has such a structure that metallic pipes 114are arranged in the form of array, and predetermined heat-resistant andanticorrosive filling materials (filler) 115 are filled up around themetallic pipes 111. The diameter of the metallic pipe 111 is the samewith or little smaller than the wavelength of the electromagnetic wave;and the length, at least 2 times longer than the wavelength. In thiscondition, the electromagnetic radiation cannot pass through theelectromagnetic wave filter 111, and the electromagnetic wave filterworks as a filter (shield) of stopping the passage of theelectromagnetic radiation. The wavelength of the microwave correspondingto the aforementioned frequency of 2.45 GHz is about 10 cm so that theelectromagnetic wave filter can be prepared by simply bundling manypipes of about 10 cm in diameter and about 30 cm in length.

[0108] Because of this constitution, the electromagnetic wave filter 111doesn't let the electromagnetic radiation but let exhausted gas(combustion gas) pass through. In this case, the property of metallicmaterials that reflect electromagnetic radiation and don't letelectromagnetic radiation pass through is made use of. However, in thecase that the temperature of combustion gas is high and that metals arein danger of corroding, the surface thereof maybe coated withhigh-temperature resistant (heat resistant) and anticorrosive materialsuch as ceramic or the like.

[0109] Further, it is known as a result of the past experiments thatdioxins contained in fly ashes are hard to be decomposed even attemperatures higher than the decomposition temperature of dioxinscontained in the combustion gas.

[0110] In the present invention, a high decomposition efficiency (ratio)is expected in decomposing not only dioxins contained in combustion gasbut also dioxins contained in fly ashes because the residence time inthe incinerator of electromagnetic wave applied to fly ashes is expectedlonger than that of electromagnetic wave applied to combustion gas. Ofcourse, the above embodiment can be modified in such a way that anelectromagnetic wave irradiation unit is placed so as to be able todirect electromagnetic radiation to the facility where fly ashes 109 areaccumulated as discussed in the following 3rd example.

[0111] Another example of the present invention is explained below. FIG.3 is a view showing the constitution of the 2nd example of the inventiveelectromagnetic incinerator 200. Refuse contains various chemicalsubstances. Consequently, the kind of toxic substances produced in thecourse of combustion is also varied in the nature of things. The 2ndexample of the inventive electromagnetic incinerator is applicable inthe case of decomposing not only dioxins but also other chemicallysynthesized products showing, e.g., high carcinogenicity. The molecularstructure of dioxins basically contains a benzene ring as shown in theabove. Benzene in itself shows very high carcinogenicity, and thedecomposition of benzene using incinerators or the like is also wanted.

[0112] In the 2nd example of the inventive electromagnetic incinerator,dioxins and benzene can be decomposed by applying electromagnetic wave(microwave) having a frequency (or frequencies) resonant with a benzenering. Accordingly, it is necessary to apply microwave of frequencieseach resonant with different chemical substance in order to treat allthe different chemical substances at the same time. In order to satisfythis requirement, different electromagnetic wave oscillators each ofwhich oscillates electromagnetic wave having a different frequency fromeach other or from one another may be provided. In order to keep theintensity of electromagnetic wave uniformly in the incinerator, aplurality of oscillators may be provided which oscillate electromagneticwave having the same frequency. FIG. 3 shows 3 electromagnetic waveoscillators 203-1, 203-2 and 203-3 provided. Of course, theseoscillators may oscillate electromagnetic wave of a different frequencyfrom one another.

[0113] Further, a stirring fan 218 may be placed and rotated in theincinerator to spread combustion gas and electromagnetic wave throughoutthe incinerator as uniformly as possible. Thus the microwave is spreadall over the combustion gas 212. This makes all the combustion gas 212exposed to microwave. A motor 217 rotates to drive the fan 218.

[0114] Moreover, a cavity 214 for applying electromagnetic wave(microwave) may be placed in the midway of a chimney section 205 (i.e.,chimney or a guide conduit to the chimney) to apply electromagnetic waveoscillated by the electromagnetic wave oscillator 203-2 to combustiongas contained in the cavity 214.

[0115] Inside the cavity 214, the magnitude of the electromagnetic wavebecomes very strong. As a result, selective heating of dioxins, benzeneor the like is done more effectively.

[0116] Still more, a system is connected to the incinerator that detectsa substance contained in the gas exhausted out of the incinerator with asensor 215 placed in, for example, the chimney section 205, analyzes thedetected result on real time using an output control unit 216, andcontrols the output of the electromagnetic wave oscillator 203-3 or else(electromagnetic radiation power) according to the analyzed result. Theoutput control unit 216 performs such feedback control that the outputpower of the electromagnetic wave oscillator 203-3 is increased in casethat the concentration of dioxins is higher than a reference value, anddecreased in case that the concentration of dioxins is lower than areference value. By this constitution of the system, the decompositionby combustion can be promoted more effectively.

[0117] Next, the wall 202 structure of the incinerator 202 will beexplained below. The wall of the conventional incinerator is made ofheat resistant, anticorrosive material (mainly ceramic or refractorymaterial). But, in general, it doesn't absorb microwave so much.Accordingly, microwave is in danger of leaking out through the wall. Theincinerator of the present invention has a radiation shielding structurethat the inside wall is a ceramic refractory wall and the outside wallis made of radiation shielding material (metallic wall). Further, theinside wall is preferably made of materials absorbing little microwaveradiation.

[0118]FIG. 4 is a view showing the constitution of the inventive refuseincinerator employed in the following 3rd example. Referring to FIG. 4,the refuse incinerator of the present invention employed in the 3rdexample has constitution that electromagnetic wave is directed from anelectromagnetic wave oscillator 302-2 through an electromagneticwave-guide 314 to fly ashes 309 and decomposes dioxins contained in thefly ashes 309 by heating up to high temperatures. In this case, astirrer for stirring the fly ashes 309 may be provided. Theelectromagnetic wave-guide 314 has a lot of electromagnetic irradiationports (holes) covered with electromagnetic wave permeating materials onthe side and at the end.

[0119] Further, with regard to the constitution of applyingelectromagnetic wave to combustion gas generated and held in theincinerator, it is needless to say that plural wave-guides having thesame constitution of the wave-guide 314 may be arranged inside theincinerator together with a ceramic window 304 through whichelectromagnetic wave is applied to combustion gas inside theincinerator. Accordingly, the incinerator of the present invention mayhave such constitution that one or more electromagnetic wave-guides,which is/are a part of electromagnetic irradiation means and shortenedto “wave-guide” sometimes, may be placed in the incinerator the insideof which is filled with combustion gas 312 during combustion, wherebyelectromagnetic wave is applied through the irradiation ports of theelectromagnetic wave-guide to the combustion gas. In this case, theirradiation ports of the wave-guide are sealed with an electromagneticwave permeating material as hereinabove mentioned in order that thecombustion gas doesn't flow upstream toward the electromagnetic waveoscillator side. Furthermore, the electromagnetic wave-guide 314 on theportion placed in the incinerator is coated by heat resistant,anticorrosive materials.

[0120]FIG. 5 is a view showing the constitution of the inventive refuseincinerator employed in the following 4th example. Referring to FIG. 5,the refuse incinerator of the present invention employed in the 4thexample has therein a cavity 414 for applying electromagnetic wavetermed as “electromagnetic wave cavity”. Combustion gas 412 generatedand held in the incinerator is introduced into the cavity 414 located inthe incinerator with a suction means such as a fan 415 or the like.Electromagnetic wave output by an electromagnetic wave oscillator 403 isapplied to the combustion gas introduced into the cavity 414.Thereafter, the combustion gas is discharged out of the cavity 414. Apart of the discharged gas is recycled again into the cavity 414 andexposed to the electromagnetic wave output by the oscillator 403 torepeat the process of decomposing and removing dioxins. Thereby theremoval ratio of dioxins is improved. The rest part of the dischargedgas is exhausted through an electromagnetic wave (shielding) filter 411as incineration gas.

[0121]FIG. 5 focuses only on the cavity 414 and the oscillator 403 inorder to explain the feature of the 4th example of the presentinvention. However, another electromagnetic wave oscillator may beplaced to direct electromagnetic radiation through a ceramic windowtoward the inside of the incinerator in the same way as the constitutionshown in FIG. 1 as a matter of course. Further, it is needless to saythat the number of the combination of the cavity 414 and the oscillator403 is not limited to one, but plural pairs of the combinations arepossible. Moreover, a passage of gas formed inside the cavity 414 may becurved to increase the residence time of gas, and a duct for guiding gasmay be attached if necessary.

[0122] of course, it is possible to combine freely the constitutions ofthe above examples shown in FIGS. 1 and 2 to 4, for example, in such away as to facility a cavity for applying magnetic wave inside theincinerator and chimney.

[0123] The present invention is applicable to a refuse incinerator andalso to incinerators of exclusive use, for example, the herbicideincinerator of the United States Air Forces that was used in the pasttime. In these incinerators, the concentration of chemical substances tobe decomposed by combustion is high so that high efficiency of thedecomposition can be expected. The present invention is also applicableto the treatment of PCB (polychlorinated biphenyl) or the like that isput in question now.

[0124]FIG. 6 is a view showing the constitution of the inventive refuseincinerator employed in the following 5th example. Referring to FIG. 6,the refuse incinerator of the present invention employed in the 5thexample has a re-combustion (after-burning) chamber 620 for inputtingand re-combusting combustion gas discharged out of the incinerator inthe midway of a chimney 605. The gas re-combusted in the re-combustionchamber 620 is exhausted through an electromagnetic wave filter 611 outof the opening of the chimney 605. Into the re-combustion chamber 620,fuel and air are fed through a fuel nozzle 621. The efficiency ofremoving dioxins can be improved by burning combustion gas again at hightemperatures in this way.

[0125]FIG. 7 is a view showing the constitution of the inventive refuseincinerator employed in the following 6th example. Referring to FIG. 7,in the refuse incinerator of the present invention employed in the 6thexample, electromagnetic wave is directed out of an electromagnetic waveoscillator 703-1 to the inside of the re-combustion chamber 720. There-combustion chamber 720 may have a cavity-like structure.

[0126] The re-combustion chamber 720 is placed before electromagneticwave arriving at the electromagnetic wave filter 711, and discharged gasis exhausted through the filter 711 after removal of dioxins by applyingelectromagnetic wave.

[0127]FIG. 8 is a view showing the constitution of the inventive refuseincinerator employed in the following 7th example. Referring to FIG. 8,in the refuse incinerator of the present invention employed in the 7thexample, a specific cavity (subcavity) 814 is installed. A fan 818rotated by driving a motor 817 positioned outside the incinerator andfunctioning as circulating combustion gas is placed near the cavity insuch a way that the rotation axis of the fan 818 becomes horizontal withthe ground. Combustion gas 812 generated and held in the incinerator isintroduced into the cavity 814 and exposed inside the cavity 814 toelectromagnetic wave output by an electromagnetic wave oscillator 803-1.The combustion gas discharged out of the cavity 814 via outlet ports(not shown) is charged again into the cavity 814 with the fan 818. Thus,combustion gas is circulated to improve the efficiency of decomposingdioxins. In the refuse incinerator of the present invention employed inthe 7th example, fuel may be introduced into the cavity to burncombustion gas again.

[0128]FIG. 9 is a view showing the constitution of the inventive refuseincinerator employed in the following 8th example. Referring to FIG. 9,the refuse incinerator of the present invention employed in the 8thexample is the same with that employed in the above 5th example shown inFIG. 6 except that a magnetizer is added. A magnet field generator(magnet) 925 is placed around a re-combustion chamber 920 to formmagnetic field inside the chamber 920. The inside of the chamber 920 isexposed to electromagnetic wave emitted by an electromagnetic waveoscillator 903-1. By the magnetic field formed inside the chamber 920,the absorption of electromagnetic wave into combustion gas increases.Thereby, the efficiency of removing dioxins contained in the combustiongas is improved. The chamber 920 is comprised of a cavity for applyingelectromagnetic wave. It is preferable that this cavity at least on theinner face thereof has the surface of material that exhibits a functionof catalytic decomposition or a coating layer made of catalyticmaterial. The object is to promote the decomposition by applyingelectromagnetic wave and also to prevent undecomposed residues fromsticking on the inner surface of the cavity and from scattering, whichsometimes occurs. The catalytic material is suitably selected fromPt-group elements, other catalytic compounds and substances.

[0129]FIG. 10 is a view showing the constitution of the inventive refuseincinerator employed in the following 9th example. Referring to FIG. 10,the refuse incinerator of the present invention employed in the 9thexample is the same with that employed in the above 7th example shown inFIG. 7 except that a magnetizer is added. A magnetizer 1025 (magnet) isinstalled in a cavity 1014 placed in the incinerator, thereby theabsorption of electromagnetic wave into combustion gas increases. As forthe magnetizer 1025, an electromagnet is preferably used, whereas apermanent magnet may be used of cooled and kept at temperatures of notmore than its Curie temperature. Alternatively, the cavity 1014 may bedisposed partly outside/partly inside the incinerator wall 1002, or justoutside the wall 1002, so far as the recirculation of the combustion gasis assured, e.g., via a returning conduit (not shown). Note, the sameapplies also to the embodiments of FIG. 8 or FIG. 5.

[0130] In all the above examples, dioxins is taken up as a chemicalsubstance to be treated. However, other chemical substances can betreated similarly, i.e., as explained in the above by determiningsuitably a resonance frequency and/or modifying fittingly otherconditions depending on the kind of chemical substances according to theprinciple employed and explained in the present invention.

[0131] The scope of the invention is not restricted to the disclosedembodiments, and it is intended that all changes based on the appendedclaims, the embodiments of the invention, elements and parts disclosedin the examples are embraced in the scope of the invention.

[0132] The meritorious effect of the present invention are summarized asfollows.

[0133] As explained in the above, according to one aspect of the presentinvention, harmful substances such as dioxins can be removed effectivelyat low costs. Accordingly, the value of the present invention is verygreat from a practical standpoint.

[0134] Further, according to one aspect of the present invention,specific chemical substances such as dioxins can be selectively heatedand decomposed. This means that raising combustion temperature becomesunnecessary in case of applying the technology essentially employed inthe present invention in a refuse incinerator. Accordingly, costs andenergy can be reduced, and the life of the incinerator can be prolonged.

[0135] Moreover, according to one aspect of the present invention, theabsorption of electromagnetic wave can be increased by forming magneticfield inside a chamber with a magnetizer and at the same time byapplying electromagnetic wave to remove harmful substances such asdioxins effectively.

[0136] It should be noted that other objects, features and aspects ofthe present invention will become apparent in the entire disclosure andthat modifications may be done without departing the gist and scope ofthe present invention as disclosed herein and claimed as appendedherewith.

[0137] Also it should be noted that any combination of the disclosedand/or claimed elements, matters and/or items may fall under themodifications aforementioned.

What is claimed is:
 1. A treating process comprising the steps of:providing an electromagnetic wave generator, and applyingelectromagnetic wave to a chemical substance and/or a materialcontaining same to selectively heat said chemical substance, therebydecomposing and purging said chemical substance.
 2. The process asdefined in claim 1, wherein said chemical substance is at least oneselected from a group consisting of dioxins, benzene, substitutedbenzene, and polychlorinated biphenyl (PCB).
 3. The process as definedin claim 1, wherein the frequency or at least one of frequencies of saidelectromagnetic wave is resonant with said chemical substance.
 4. Theprocess as defined in claim 2, wherein the frequency or at least one offrequencies of said electromagnetic wave is resonant with said chemicalsubstance.
 5. A dioxins-treating process comprising the step of:providing an electromagnetic wave oscillator, and applyingelectromagnetic wave to dioxins and/or a material containing dioxins toheat selectively dioxins, thereby decomposing and removing dioxins.
 6. Adioxins-treating process comprising the steps of: providing anincinerator generating a combustion gas and an electromagnetic waveoscillator, and applying electromagnetic wave to the combustion gas byintroducing the electromagnetic wave into said incinerator toselectively heat dioxins contained in said combustion gas, therebydecomposing and removing dioxins.
 7. A dioxins-treating processcomprising the steps of applying electromagnetic wave to fly ashesgenerated and in an incinerator and selectively heating dioxinscontained in said fly ashes, thereby decomposing and removing dioxins.8. The process as defined in claim 5, wherein said electromagnetic wavehas at least a frequency of microwave resonant with the dioxins.
 9. Theprocess as defined in claim 6, wherein said electromagnetic wave has atleast a frequency of microwave resonant with the dioxins.
 10. Theprocess as defined in claim 7, wherein said electromagnetic wave has atleast a frequency of microwave resonant with the dioxins.
 11. Anincineration treatment apparatus comprising an electromagnetic waveoscillator, wherein electromagnetic wave emitted from said oscillator isintroduced into an oven to irradiate the electromagnetic wave todioxins-containing combustion gas.
 12. The apparatus as defined in claim11, which further comprises a chimney section for discharging saidcombustion gas and an electromagnetic wave filter therein for preventingelectromagnetic radiation from passing through.
 13. The apparatus asdefined in claim 12, which further comprises a cavity for applyingelectromagnetic wave positioned in said chimney section upstream of saidfilter, wherein said combustion gas generated in said incinerator isintroduced into said cavity, exposed inside said cavity toelectromagnetic wave emitted by said electromagnetic wave oscillator,and thereafter discharged as incineration gas through said filter. 14.The apparatus as defined in claim 12, wherein said electromagnetic wavefilter is equipped with plural metallic hollow pipes each beingopen-ended and aligned in the flowing direction of said combustion gas,the diameter of said pipe being smaller than the wavelength of saidelectromagnetic wave, and the length of said pipe being longer than saidwavelength.
 15. The apparatus as defined in claim 13, wherein saidelectromagnetic wave filter is equipped with plural metallic hollowpipes each being open-ended and aligned in the flowing direction of saidcombustion gas, the diameter of said pipe being smaller than thewavelength of said electromagnetic wave, and the length of said pipebeing longer than said wavelength.
 16. The apparatus as defined in claim11, which further comprises: a sensor detecting the concentration ofdioxins contained in an exhausted gas; and an output control unitoutputting a control signal for variably controlling the magnitude ofelectromagnetic wave applied to combustion gas generated in saidincinerator depending on the output of said sensor, wherein saidelectromagnetic wave oscillator receives said control signal from saidoutput control unit and changes the output power of electromagneticwave.
 17. The apparatus as defined in claim 12, which further comprises:a sensor detecting the concentration of dioxins contained in anexhausted gas; and an output control unit outputting a control signalfor variably controlling the magnitude of electromagnetic wave appliedto combustion gas generated in said incinerator depending on the outputof said sensor, wherein said electromagnetic wave oscillator receivessaid control signal from said output control unit and changes the outputpower of electromagnetic wave.
 18. The apparatus as defined in claim 13,which further comprises: a sensor detecting the concentration of dioxinscontained in an exhausted gas; and an output control unit outputting acontrol signal for variably controlling the magnitude of electromagneticwave applied to combustion gas generated in said incinerator dependingon the output of said sensor, wherein said electromagnetic waveoscillator receives said control signal from said output control unitand changes the output power of electromagnetic wave.
 19. The apparatusas defined in claim 14, which further comprises: a sensor detecting theconcentration of dioxins contained in an exhausted gas; and an outputcontrol unit outputting a control signal for variably controlling themagnitude of electromagnetic wave applied to combustion gas generated insaid incinerator depending on the output of said sensor, wherein saidelectromagnetic wave oscillator receives said control signal from saidoutput control unit and changes the output power of electromagneticwave.
 20. The apparatus as defined in claim 11, which further comprisesa fan for stirring the combustion gas and the electromagnetic wave insaid incinerator, and a motor for driving said fan.
 21. The apparatus asdefined in claim 13, which further comprises a fan for stirring thecombustion gas and the electromagnetic wave in said incinerator, and amotor for driving said fan.
 22. The apparatus as defined in claim 11,which further comprises an electromagnetic irradiation unit applyingelectromagnetic wave to fly ashes in said incinerator.
 23. The apparatusas defined in claim 12, which further comprises an electromagneticirradiation unit applying electromagnetic wave to fly ashes in saidincinerator.
 24. The apparatus as defined in claim 13, which furthercomprises an electromagnetic irradiation unit applying electromagneticwave to fly ashes in said incinerator.
 25. The apparatus as defined inclaim 16, which further comprises an electromagnetic irradiation unitapplying electromagnetic wave to fly ashes in said incinerator.
 26. Theapparatus as defined in claim 22, which further comprises anelectromagnetic irradiation unit applying electromagnetic wave to flyashes in said incinerator.
 27. The apparatus as defined in claim 11,wherein an inside wall of said incinerator is made of ceramics, and anoutside wall of the incinerator is made of electromagnetic radiationshielding metal.
 28. The apparatus as defined in claim 11, wherein arefuse input port and a fly ash output port of said incinerator have adouble door structure.
 29. The apparatus as defined in claim 11, whichfurther comprises a cavity for applying electromagnetic wave inside saidincinerator, wherein said combustion gas in said incinerator isintroduced into said cavity, exposed inside said cavity toelectromagnetic wave emitted by said electromagnetic wave oscillator,and thereafter discharged out of said cavity, a part of the dischargedgas is introduced into said cavity again, and exposed to saidelectromagnetic wave, and the rest part of the discharged gas isexhausted as incineration gas through an electromagnetic wave filter.30. The apparatus as defined in claim 13, which further comprises acavity for applying electromagnetic wave inside said incinerator,wherein said combustion gas in said incinerator is introduced into saidcavity, exposed inside said cavity to electromagnetic wave emitted bysaid electromagnetic wave oscillator, and thereafter discharged out ofsaid cavity, a part of the discharged gas is introduced into said cavityagain, and exposed to said electromagnetic wave, and the rest part ofthe discharged gas is exhausted as incineration gas through anelectromagnetic wave filter.
 31. The apparatus as defined in claim 12,which further comprises a cavity for applying electromagnetic waveinside said incinerator, wherein said combustion gas in said incineratoris introduced into said cavity, exposed inside said cavity toelectromagnetic wave emitted by said electromagnetic wave oscillator,and thereafter discharged out of said cavity, a part of the dischargedgas is introduced into said cavity again, and exposed to saidelectromagnetic wave, and the rest part of the discharged gas isexhausted as incineration gas through an electromagnetic wave filter.32. The apparatus as defined in claim 22, which further comprises acavity for applying electromagnetic wave inside said incinerator,wherein said combustion gas in said incinerator is introduced into saidcavity, exposed inside said cavity to electromagnetic wave emitted bysaid electromagnetic wave oscillator, and thereafter discharged out ofsaid cavity, a part of the discharged gas is introduced into said cavityagain, and exposed to said electromagnetic wave, and the rest part ofthe discharged gas is exhausted as incineration gas through anelectromagnetic wave filter.
 33. The apparatus as defined in claim 11,wherein at least one oscillator emitting electromagnetic wave ofmicrowave band resonant with dioxins or dioxins and benzene is installedas an electromagnetic wave oscillator.
 34. A refuse incineratingapparatus comprising the incineration treatment apparatus as defined inclaim
 11. 35. A refuse incinerating apparatus comprising theincineration treatment apparatus as defined in claim
 13. 36. A refuseincinerating apparatus comprising the incineration treatment apparatusas defined in claim
 16. 37. A refuse incinerating apparatus comprisingthe incineration treatment apparatus as defined in claim
 29. 38. Arefuse incinerating apparatus comprising the incineration treatmentapparatus as defined in claim
 33. 39. The apparatus as defined in claim11, which further comprises a re-combustion chamber for inflowing andre-combusting said combustion gas, wherein the resultant gasre-combusted in said chamber is exhausted.
 40. The apparatus as definedin claim 12, which further comprises a re-combustion chamber forinflowing and re-combusting said combustion gas, wherein the resultantgas re-combusted in said chamber is exhausted.
 41. The apparatus asdefined in claim 39, wherein electromagnetic wave oscillated by saidoscillator is applied to the inside of said chamber.
 42. The apparatusas defined in claim 41, wherein said chamber is disposed in said chimneysection.
 43. The apparatus as defined in claim 11, which furthercomprises: a cavity positioned in said incinerator; and a fan near saidcavity, said fan being driven by a motor positioned outside saidapparatus; wherein said combustion gas in said incinerator is introducedinto said cavity, exposed inside said cavity to electromagnetic waveemitted by said electromagnetic wave oscillator, and introduced againinto said cavity to circulate after being discharged out of said cavity.44. The apparatus as defined in claim 43, wherein fuel is introduced insaid cavity to re-combust said combustion gas.
 45. The apparatus asdefined in claim 41, wherein said re-combustion chamber is provided witha magnetizer for forming magnetic field inside said re-combustionchamber.
 46. The apparatus as defined in claim 41, wherein saidre-combustion chamber has a cavity for applying electromagnetic wave.47. The apparatus as defined in claim 41, wherein said cavity isprovided with a magnetizer for forming magnetic field inside saidcavity.
 48. A refuse incinerating apparatus comprising the incinerationtreatment apparatus as defined in claim 40 as an incinerator.
 49. Theapparatus as defined in claim 29, wherein said cavity has at least onthe inner face thereof a surface of catalytic material or a coatinglayer of catalytic material.
 50. The apparatus as defined in claim 43,wherein said cavity has at least on the inner face thereof a surface ofcatalytic material or a coating layer of catalytic material.
 51. Adioxins-treating process comprising the steps of: introducing combustiongas of a refuse incinerator into a chamber, exposing the combustion gasto electromagnetic wave to selectively heat dioxins contained therein,and meanwhile applying magnetic field to the combustion gas to decomposeand remove dioxins.